Conclusions

The inverse-square law derived perceived size equation, especially the simplified perceived height equation, has been proven to be able to accurately calculate size perception. The experiments have substantiated that, unlike the traditional accounts of optical geometry and SDIH, the terms in the new equation have the precisely measured values. The term, measure-point, has set the new equation apart from any other mathematical expressions of size perception. Actually, the term M_p plays an essential role in our size perception. The measure-point can help explain some perplexing phenomena of size perception, e.g., the phenomenon that the objects in a second mirror appear smaller when the mirror is moved closer to the eye. The measure-point is potentially a key factor for understanding the size illusions such as the Ames room illusion and moon illusion, the Emmert’s law, and size/shape constancy.

The main finding of the investigations is that mirror images do not have the extra-mental existence because the calculations of the perceived size of the mirror images and follow-up experiments have revealed that the image in the first mirror does not show up in the second mirror. The further analysis and reasoning tell us that ordinary objects, like mirror images, might be the projected images as well. If this claim were true, we could live in a projected world, rather than in an objective world as we have known and believed.

The mind is believed to be different from the brain in essence. The mind is non-physical so that it can mentally project images instantaneously whereas it is impossible for the physical brain to project anything faster than the speed of light. The mental projection, even just of the mirror images, precludes any possibility of direct perception of any kind because there is no mirror image reaching the retina. The possibility of representational perception is also excluded because the brain simply cannot construct the physical replicas of the external objects which are mind-dependent themselves.

Finally, the conventional outside-in understanding of vision may have to be replaced by the inside-out conception, that is, the mind is the source and the projected image is the end-product of perception.

The findings presented in this paper may have assaulted our common sense and sounded quite counter-intuitive; but the truth is beautiful. To know that we might live in a projected world does not make the world we live in any less wonderful. As a matter of fact, this knowledge may make everyone feel being intimately in touch with everything else in the universe because they are intrinsically related to our mind. We are the world and the world is inside us.